Introduction

Sam Harris' Free Will isn't a conventional philosophy book. Rather, it's a laconic manifesto full of bold and provocative statements invoking us to free ourselves from the delusion of free will and abolish the whole concept as misleading and unnecessary. The book quickly shatters the naïve layperson’s intuition in the light of scientific advancements, then briefly explains Harris’ dissatisfaction with compatibilism as a half measure, and finally argues that our morality, penal and political systems would only benefit from the dispelling of the illusion which the “free will” is.

Or at least it's what the book tries to be. For me, however, it turned out to be something different. While my initial craving for deep arguments in favour of a position I disagree with wasn’t satisfied, I got interesting insight from Harris' attempts at resolving confusion and reinventing existing theories with different aesthetics. Most surprisingly, I got a new perspective on religious tolerance. Predictably, the publication of the book led to a philosophical debate on the matter of free will between Sam Harris and Daniel Dennet which turned out to be larger than the book itself. I’ll touch it a little in this review as well.

Main thesis

Harris begins his book with a description of a terrible crime. He points out how our perception of this crime can be shifted if we are informed of the underlying causes. But, under scrutiny, these causes go beyond the control of any of the perpetrators, leaving no extra place for their personal responsibility. He uses it as a high stakes example to make his point.

Of course, if we learned that both these men had been suffering from brain tumors that explained their violent behavior, our moral intuitions would shift dramatically. But a neurological disorder appears to be just a special case of physical events giving rise to thoughts and actions. Understanding the neurophysiology of the brain, therefore, would seem to be as exculpatory as finding a tumor in it. How can we make sense of our lives, and hold people accountable for their choices, given the unconscious origins of our conscious minds? 

And therefore he concludes:

Free will is an illusion. Our wills are simply not of our own making. Thoughts and intentions emerge from background causes of which we are unaware and over which we exert no conscious control. We do not have the freedom we think we have.

Calling Sam Harris a hard determinist seems to be an understatement. Not only does he claim that freedom of will is incompatible with determinism or causality, he claims that it's an inherently incoherent concept in any reasonable universe.

It is important to recognize that the case I am building against free will does not depend upon philosophical materialism (the assumption that reality is, at bottom, purely physical). There is no question that (most, if not all) mental events are the product of physical events. The brain is a physical system, entirely beholden to the laws of nature—and there is every reason to believe that changes in its functional state and material structure entirely dictate our thoughts and actions. But even if the human mind were made of soul-stuff, nothing about my argument would change. The unconscious operations of a soul would grant you no more freedom than the unconscious physiology of your brain does.

 

Free will is actually more than an illusion (or less), in that it cannot be made conceptually coherent. Either our wills are determined by prior causes and we are not responsible for them, or they are the product of chance and we are not responsible for them.

Harris doesn’t let the popular view that free will somehow benefits from randomness or unpredictability slow him down. Later, he mentions the idea of randomly occurring “self-generated” events in the brain as a justification of free will and quickly dispatches it.

If my decision to have a second cup of coffee this morning was due to a random release of neurotransmitters, how could the indeterminacy of the initiating event count as the free exercise of my will? Chance occurrences are by definition ones for which I can claim no responsibility. And if certain of my behaviors are truly the result of chance, they should be surprising even to me. How would neurological ambushes of this kind make me free?

 

In the limit, Heisenberg’s “self-generated” mental events would preclude the existence of any mind at all.

I think this is a good point, and appreciate that it was mentioned. Too much conventional discourse is focused on arguing whether determinism is compatible with free will, even though indeterminism is much more at odds with it. One may even notice that if the existence of the mind and its decision making properties requires an ordered universe, this is an evidence in favor of compatibilism

Not Harris, though. While he acknowledge that such qualities as planning for the future, weighting competing desires and conscious awareness are real, and distinguishes voluntary and involuntary decisions, he explicitly states that they have "nothing to do with free will".

Which is a shame. His original claim seemed so bold and strong. But if someone excludes from a definition everything that exists, while including inner contradictions, it is no wonder that we will find the concept to be not real and incoherent. To a degree it can be justified by the fact that Harris is arguing against a naïve layperson’s intuition about free will. But to a more sophisticated reader it can seem bizzare. As though Sam Harris is annoyed by the concept of the present, for instance.

I cannot decide what I will next think or intend until a thought or intention arises. What will my next mental state be? I do not know—it just happens. Where is the freedom in that?

Dealing with confusion

I’d say that Sam Harris is much less confused about free will than most. Not only is he aware of his own confusion, to a point that he can write a book about it, he makes an actual attempt to resolve it. Harris does try to reduce free will to the feeling that “arises from our moment-to-moment ignorance of the prior causes of our thoughts and actions”.  He even grapples with the concept of could-ness:

However, to say that I could have done otherwise is merely to think the thought “I could have done otherwise” after doing whatever I in fact did. This is an empty affirmation.

This is commendable, but not near enough to get an actual insight for a gears-level model of free will. The quotation is not the referent. He doesn't taboo the word "could", doesn't try to figure out the reason for this feeling to exist and what role it plays in our decision making. Excluding decision-making from the concept doesn't help.

Harris is good at pointing out incoherences in other people's reasoning, however, as represented in the book, his own position doesn't seem to be very coherent either. In one place he can claim that such concepts as counterfactuals or responsibility are meaningless, and in the other he uses them himself. When he claimed that "losing a belief in free will  has increased his feelings of freedom" -  I had serious troubles parsing the statement.  May it be him trying to speak to the audience in their own language? But the most obvious incoherence is highlighted when Harris argues against compatibilism only to prove its core points later.

Harris condemns compatibilism as "solving the problem of free will by ignoring it"; changing the definition of free will  to one people don’t actually use. He even compares compatibilism to theology.

Compatibilists have produced a vast literature in an effort to finesse this problem. More than in any other area of academic philosophy, the result resembles theology. (I suspect this is not an accident. The effort has been primarily one of not allowing the laws of nature to strip us of a cherished illusion.)

I think it tells us something important about Harris' reasons for embracing his views. He treats the concept of free will similarly to the concept of God. For him both are confusing, naive intuitions which do not correspond to reality and lead people astray. And if the correct answer to question of theology is to say that God doesn’t exist, whole idea doesn’t actually make any sense, and that we shall all be better without it, grounding our morality and sense of meaning in the real world instead of imaginary entities – why wouldn’t the same be true for the question of free will? Isn’t  Sam Harris just applying consistent strategy to deal with apparently mysterious phenomena?

Except, when he is not.  As Daniel Dennet mentions in his own review to the book, that’s not the course of action Harris takes regarding the concept of mind. He corrects the naïve definition rather than abolishing it. And it’s not what we do in general. An even better example from the same review is sunsets. Now, when we know that geocentrism is wrong and the sun doesn’t actually rise and set, we haven’t got rid of the concept calling it illusion, we’ve changed the definition.

Is it possible to develop a simple consistent policy on what to do when we find out that a definition doesn’t actually make any sense in the light of new evidence? I’m not sure. My intuition is against attempts to reframe “God” as a sense of meaning, compassion and oneness but completely supports the compatibilist definition of free will. Is it the fact that I perceive the concept of God to be too contaminated, unlike the concept of free will? But other people's intuitions can differ which doesn't necessery make them wrong.  If anything, this becomes not a question of fact but of a category border

And this is a good cause for tolerance. For the last couple of years I had problems talking to religious people. I've noticed that I approached them with a smug feeling of superiority, despite my best efforts to be charitable. "Pretend all you want, but you actually know that you are completely right and they are completely wrong" - some voice deep inside me was saying. Trying to persuade myself that it's noble and good to be tolerant, even towards silly ideas, was fruitless. But framing this as a question of a category border really helped to be genuinely curious. My opponents may be wrong about some things, but understanding their worldview and their way to define categories can give valuabale insights about things that I may have been missing. The fact that I got this insight due to Sam Harrris' book is both ironic and very appropriate.

Moral and political implications

I've always had an intuition that hard determinist views are usually a result of painful disenchantment with metaphysical libertarianism. Finding out that their naive intuition of free will is incoherent and/or doesn’t correspond to reality, people swing in the opposite direction, claiming that no free will is possible. However, I get a different feeling from Sam Harris. He seems to be entirely satisfied with the absence of free will, and he spends the last part of the book proclaiming how great it is.

My hopes, fears, and neuroses seem less personal and indelible. There is no telling how much I might change in the future. Just as one wouldn’t draw a lasting conclusion about oneself on the basis of a brief experience of indigestion, one needn’t do so on the basis of how one has thought or behaved for vast stretches of time in the past. A creative change of inputs to the system—learning new skills, forming new relationships, adopting new habits of attention—may radically transform one’s life.

Harris is optimistic that abolishing the concept of free will and therefore metaphysical responsibility and religious sin is going to dramatically improve the criminal justice system, moving its focus from retribution to correction. He is talking from consequentialist position here and I share his moral intuition about the utility of such change. His chapter on political implications mentions that without the illusion of free will, it would be much more obvious how much luck is responsible for personal success and how absurd the conservative "fetish of individualism" is. Such changes would indeed be beneficial, but I'm not sure that abolishing the concept would do the trick. And actually, neither is Harris, at least not completely:

 It must be admitted, however, that the issue of retribution is a tricky one. In a fascinating article in The New Yorker, Jared Diamond writes of the high price we sometimes pay when our desire for vengeance goes unfulfilled.

 

We are deeply disposed to perceive people as the authors of their actions, to hold them responsible for the wrongs they do us, and to feel that these transgressions must be punished. Often, the only punishment that seems appropriate is for the perpetrator of a crime to suffer or forfeit his life. It remains to be seen how a scientifically informed system of justice might steward these impulses.

I think we can apply the theological metaphor here once again. While for some people their religious beliefs are indeed the reason for their behaviour, for others it's just a rationalization for their other less socially acceptable impulses. The whole religious memeplex is built existing human intuitions in the first place. And people do not necessery act on their beliefs.  That's why raising the sanity waterline is much more important than attacking the religion directly. And that's why it's a bit naive to expect dramatic changes in the penal system due to some philosophical argument, even if, as Harris mentions, U.S. Supreme Court has indeed called free will a “universal and persistent” foundation for the system of law.

Conclusion

In the end, I was surprised how compatibalist the book turned out to be. Despite all the apparent critique of compatibalism, Harris makes mostly the same points and sometimes even uses the same language. Dennet calls him a compatibalist in everything except by name and I tend to agree. Their argument is a textbook example of disputing definitions, as they seem to agree on every objective matter. If we define C-freedom as agency and choice-making ability of the mind, which depends on the causal history, and L-freedom as transcending the laws of causality by being the ultimate source of one's actions, both Harris and Dennet agree that humans have C- but not L-freedom, and that it doesn’t lead to fatalism. 

In a sense Sam Harris has reinvented compatibilism. He comes to the same conclusions but is rallying under the flag of “Free Will Doesn’t Exist”. And while this approach seems unnecessary to me, I suppose it's a valid one.  I'd say in this case Harris is free to define his terms the way he wants. 

Or rather... not free - if that's what he prefers.  

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Harris does try to reduce free will to the feeling that “arises from our moment-to-moment ignorance of the prior causes of our thoughts and actions”.

I like this. Free will is the feeling when you don't know the causes of your thoughts and actions.

However, to say that I could have done otherwise is merely to think the thought “I could have done otherwise” after doing whatever I in fact did.

To say that I could have done otherwise means that there could be a parallel reality where the unknown causes of my thoughts and actions were slightly different, and therefore produced a different outcome, and yet the ignorance before the outcome felt the same. That is, the same feeling is connected to different outcomes... in different realities. I can't use the feeling to predict the specific outcome; I can only get a distribution of likely outcomes. And yet, because I am in a specific reality, the specific outcome is determined; I just can't predict it.

(Map vs territory distinction, essentially. Free will exists on the map, not in the territory. It is not an illusion, in the sense that it is actually there on the map; without perfect self-knowledge it can't be otherwise.)

How should I feel about my lack of free will?

It is an unnecessary hypothesis; removing it doesn't change the actual calculation (except maybe for the part where you used to reflect on the fact that you were deciding, and then sometimes felt confused about the concept of free will). Just do whatever you think is the right thing to do. You see a few options you could take. Ignore the fact that one of them is already "predetermined" in some sense. The fact that you consider multiple options and choose the best one is how the "predetermined" one gets selected. It's like, when you try to calculate 123×456, the result is also predetermined, and yet you need to do the calculation to actually get it. In the same way, consider the possible consequences of the options you have, and then you will choose one, based on some combination of logic and whim that will happen in your brain at given moment.

How this relates to punishment of crime?

We assume that when the potential criminal runs their calculation to decide whether to do the crime or not, the information about the possible punishment is part of the calculation. When it is not, for example if the criminal is too retarded to even understand the concept of punishment or the fact that it would apply here... then this type of punishment just needlessly hurts the criminal, without actually providing protection for potential victims.

Note that this works even if the criminal is not aware of the specific punishment for the specific crime, only is vaguely aware that "this type of action will likely get punished somehow". That means, it also works for informal out-of-court punishment without exact data. If you punch me, you can expect me to punch you back with some probability -- you do not know the exact probability, nor the exact force, nor the chance that instead of punching you I will overreact and stab you with a knife... so there is an uncertainty... but you know that some kind of punishment is likely to happen, on average, and your estimate is a part of your calculation.

There is also another thing to consider, which is that if someone commits a crime, it can be a strong evidence that the person is likely to make a similar type of crime again, and therefore you may want to take precautions. In the extreme case, if you execute the criminal, they will never commit a crime again. You can also put the criminal in prison, put them on a blacklist, deprive them of certain rights, etc. Here, you are not trying to influence their calculation; you are taking it as given, and trying to eliminate the threat. From this perspective, you may want to execute the retarded killer, just to make sure he never kills again; but if you can put him in an institution that prevents him from killing again, that would achieve the goal equally well.

People may confuse these two things (punishment as precommitment vs removal of known threat), or they may feel that eliminating the threat is okay only if the person deserves it somehow. (To deserve = we precommitted to use punishment X against people who did Y, and this specific person did Y.) For example, if you could use a mind scanner to determine that some person will kill a random stranger with probability 99%, but the person hasn't done anything bad yet... many people would object against limiting that person's rights. (And there is a good reason for doing so -- such predictions could be wrong, and people could be motivated to make wrong predictions about those they don't like.) The really complicated case is if the person has already killed someone... in such way that precommitting to punish them wouldn't change their calculation... and is 99% likely to do it again. Then we have the conflict of principles "we shouldn't precommit to punish people for actions where our precommitment has no impact on their doing the action" and "we shouldn't eliminate the perceived threat, unless they already did something that we have precommitted to punish" (a combination of which would let an insane criminal walk free), and the common sense that says that of course this person is likely to kill again so we should use some rationalization to argue that the aforementioned principles do not apply in this case.

Shortly, if the criminal says "why are you punishing me? I have no free will", the answer is "you are deciding using an algorithm, and we have precommitted to punish people in your reference class, to influence their algorithm and reduce the total number of crimes they will commit as a group... which apparently had no effect on you specifically, given that you did the crime anyway, but will prevent some of the others from doing the same thing". Of course, if you put it this way, it will sound wrong to most people.

I mostly agree.

I like this. Free will is the feeling when you don't know the causes of your thoughts and actions.

It's definetely a huge part of the puzzle. But not all of it. Free will is also a feeling of not knowing the choices you will make in the future. And the process of determining this choice due to all the causes.

Suppose Omega perfectly knows all the prior causes of my decisions, it has my source code and all the inputs. Omega would still have to run the source code with these inputs, to actually execute my decision making algorithm, so that it can determine my actions. But nevertheless my actions are determined by my decision making algorithm. This part of free will is completely real.

(Map vs territory distinction, essentially. Free will exists on the map, not in the territory. It is not an illusion, in the sense that it is actually there on the map; without perfect self-knowledge it can't be otherwise.)

Yes! But with a caveat. This state of not knowing which action will actually be executed seems to be essential for the work of the decision making algorithm. Options need to be marked as reachable so that our tree search found the best one. Also the destinction between map and the territiry becomes fuzzy when the territory is our map making engine. Our decision making algorithm is embedded in our brain in this sense our freedom of will is more than just part of the map.

[-]TAG-40

To say that I could have done otherwise means that there could be a parallel reality where the unknown causes of my thoughts and actions were slightly different, and therefore produced a different outcome, and yet the ignorance before the outcome felt the same.

That's not what could-have-done-orherwise is generally intended to mean. It might the closest approximation you can achieve assuming determinism. But that's an assumption , not a fact.

Map vs territory distinction, essentially. Free will exists on the map, not in the territory.

If you had perfect knowledge of the territory, you would not even need the map. Again, you are treating assumptions as facts .

I think the main point that people are missing here is that Sam Harris is an experienced meditator with years of intensive retreat practice. This means that he likely routinely enters states where the perception of any "doer" or "observer" in subjective experience goes away, states where no "decision" is ever taken, but events "just happen" on their own. This is why Harris has such strong opinions on free will, advanced meditation practice will directly show you how the appearance of decisions and free will is being constructed moment-by-moment, no need for any philosophical arguments about determinism when you can simply look at your immediate experience and see it lacking any free will. I suspect he wrote the book because he couldn't just say "trust me, if you meditate for 5000 hours you'll see you have no free will", even though that would likely be a more honest answer.

I am an experienced sleeper with years of intensive practice for hours every night. I routinely experience states where the perception of anything at all goes away, states where not only "no decision" is ever taken, but where nothing even "happens".

But I do not mistake this for a deep insight into the nature of the mind. It just tells me that it can turn on and off.

Meditators, it seems, have learned to shut off parts of their mind, while leaving enough still running to be able to report on the experience afterwards. That does not mean that those parts do not exist. It just means that they have turned them off.

FWIW, I do also meditate from time to time, although I am not sure that the thing that I do that I am calling meditation is the same as the things that other people do that they call meditation (or that the things that other people do are the same as each other). Be that as it may, I don't see any more reason to credit the diminished, enhanced, or weird states that some report with any insight into reality, any more than I would credit drug experiences with the same, spontaneous episodes of religious revelation (see the case of John C. Wright), or "strokes of insight" (Jill Bolte Taylor).

The difference with sleep is that meditation increases perceptual clarity instead of decreasing it. The experience of seeing your mind turn off and on while seeing clearly everything that is happening is actually one of the most profound things that can happen in meditation because you can see in real time the different parts of the mind shutting down one by one, giving you insight into what those parts actually are.

Experiences of a lack of free will are relevant to understanding the nature of the mind because the usual presumption is that free will is somehow a property of decision-making itself, not a weird tacked-on module of the brain that can easily be dispensed with. If free will is just a thin coat of paint over the decision making module, then it's not really free will at all. Advanced meditation lets you experience making eggs in the morning, taking a jog, talking to your spouse, writing your emails all without the experience you might usually have called "free will". What was intuitively thought to be a crucial part of decision making is seen to be not necessary at all. But it's more than that, because it doesn't feel like "the free will module stopped", it feels more like "what I thought was the free will module is actually 5 other different modules, and my lack of perceptual clarity was kind of blending the 5 together in a confused mess".

Does a "free will" module in a brain make any more sense than a "speed" module in a car?

How do you tell from within whether you have shut down a module or merely averted your mental eye from the phenomenon? "There is no light," says the sceptic, turning it off. "See?"

The car does have a speed module that happens to be a good analog for a hypothetical free-will module in humans. The speedometer produces an output based on the internal workings of the vehicle. It is also an excellent example of how maps can give outputs that are not necessarily grounded in the state of the territory.

How many conditions can you think of where a driver should ignore the report of the speedometer?

It sounds like you put a higher weight of probability on "meditators can turn off or ignore a brain module that let's them sense their free will" than "meditators can learn to turn off or ignore a brain module that applies a narrative of free will to a deterministic process".

Is that correct? If so, why?

I don't put any weight of probability (including 0) on either of these. Both depend on presuppositions about brain "modules" that I judge to be so far from making sense that taking either of them seriously would be privileging the hypothesis.

Where is the "speed" module in a car?

[-]TAG30

Meditation might show that one model of free will is false. Specifically, the idea of the an inner essential self which is the originator of all actions, a kind of Central Puppeteer. A self whose boundaries stop at the conscious mind, and which imagines it controls things by pre-determining them, the only kind of control Harris allows.

People are often surprised at the absence of a central Puppeteer as revealed by meditation, so it has some currency. But Harris is making a much bolder claim that disproving one, naive notion of free will. He is claiming to disprove all concepts of free will, including less naive and less demanding concepts.

The Central Puppeteer is a mirror image of the notion of selfhood that Dennet deconstructs in Consciousness explained , the Central Scrutinizer where all perceptions come together in a single definitive draft.

Dennett, in his work on consciousness, separately from his work on free will, argues that there is no central place where conscious perceptions come together in a single definitive version...no "Central Scrutinizer". Nonetheless, a kind of compatibilism is possible: the brain as a messy distributed system can , in some messy, approximate way, perceive an external world. There is perception even without an inner perceiver, and an external self -- just the John Smith, social security number so-and-so, address so-and-so -- that is known to the world at large. So maybe there is some compatibilism possible if one accepts the claim that there is no central Puppeteer.

And that self, just the total person, could be the self who is making decisions aside from the Central Puppeteer. And, indeed, decision-making still occurs. If it occurs without duress , the there is compatibilitist free will. Meditation does not show that one is always under duress!

Voluntary action of some sort is implicit in the very idea that Sam Harris is a meditator. The ability to stick to a schedule of meditatating for so many hours a day indicates that Harris does have control in some sense , he his ego or conscious mind, makes the decision to meditate, and he sticks to it, which means that he resists impulses to get up and do something else ... which itself means that having thoughts and desires and impulses present themselves in consciousness does not make him a helpless puppet of them. People with no impulse control can't function as adults. And refraining, filtering, selecting amongst promptings and impulses is a kind of control ... the other kind of control that Harris does not explicitly consider.

It is tricky to talk in self-consistent ways about lack of free will. Obviously any kind of prescriptivism is right out: since there is no free will you can't consciously steer the future in any specific direction, you can only have an illusion of it. It is possible to talk about lack of free will in descriptive terms, however. For example, a statement like "one should hold people accountable even though free will does not exist, for the benefit of the society as a whole", can be expressed as "societies where people are held accountable for their actions tend to be more successful, by some relevant metric, than those where they are not".

It is also easy to misinterpret a self-consistent view as self-contradictory, if one is not careful (this is not an urge to be careful, that would be inconsistent in itself, just an observation I had no control over talking about). For example when he says "needn't" a reader can interpret it as "shouldn't", even though that's not what he meant. I haven't read Harris's book, but my guess would be that he takes appropriate care not to sound like he does more than describing the world he sees.

I haven't read Harris's book, but my guess would be that he takes appropriate care not to sound like he does more than describing the world he sees.

I had originally expected exactly that from the book! But, in my opinion, it didn't turn out to be the case. I'm pretty sure that Harris could have done it if he intended to. My guess is that he wanted to be more relatable and appealing to a layman reader rather than polish his speech too much.

[+][comment deleted]10

What does Harris say he means by the words "free will"?

This was a great review of his book. Thank you!

This was a great review of his book. Thank you!

[-]jmh10

Just an incomplete skimming of the post but one thing seemed to jump out at me. Did Harris always cast free will as a act to do something? Did he explore the case where all the external and internal impulses to do something were then overridden by the person and a different choice made?

Like most  arguments against free will, Harris's is rhetorically incoherent, since he is "for" letting criminals off the hook when he discovers their actions are the result of determinism.  

How can we make sense of our lives, and hold people accountable [emphasis mine] for their choices, given the unconscious origins of our conscious minds? 

But if there's no such thing as free will, then it's impossible to be "for" or "against" anything, since our own actions are just as constrained as the criminal's.  What exists simply exists, no more, no less.

More importantly, his  argument is  fundamentally an argument  from ignorance: I am not aware of any philosophy that coherently explains free  will, therefore none exists.  It would do to compare arguments against free will  to Zeno's Arrow Paradox  regarding the impossibility of motion.  Zeno  argues that a arrow must be one of two things: in place, or moving, and hence it cannot be both at the same time.  We now  know that this is factually false  and the reason why Zeno believed it is likely because humans are not mentally equipped to intuitively understand quantum physics.

But if there’s no such thing as free will, then it’s impossible to be “for” or “against” anything, since our own actions are just as constrained as the criminal’s. What exists simply exists, no more, no less.

Similarly:

“It’s my fate to steal,” pleaded the man who had been caught red-handed by Diogenes.

“Then it is also your fate to be beaten,” said Diogenes, hitting him across the head with his staff.

(https://sofoarchon.com/the-philosophy-of-diogenes/)

As far as accountability for criminal actions goes, OP says that Harris’s stance is consequentialist, but it seems to me that it’s not nearly consequentialist enough.

After all, surely the question is whether holding people accountable for their actions—that is, treating them as if they had free will—does, or does not, deter crime, and otherwise reduce the negative consequences of criminal behavior (by curbing incidence, severity, or both)?

If the answer is “yes”, then we should treat criminals as if they had free will. Otherwise, not. (Setting aside, for the moment, questions of the moral permissibility, or even imperative, of retribution per se.)

That would be the true consequentialist position, I think. Harris’s view, on the other hand, seems to be rooted in a sort of naive or folk-philosophical sense of fairness, where, if you’re not “responsible” for your actions, in some (again, naively conceived) sense of the word, then you shouldn’t be punished for them. But I don’t see that this should be an axiom of our approach to justice; at best, a desideratum…

The famous Oliver Wendell Holmes quote on the matter:

If I were having a philosophical talk with a man I was going to have hanged ... I should say, I don’t doubt that your act was inevitable for you but to make it more avoidable by others we propose to sacrifice you to the common good. You may regard yourself as a soldier dying for your country if you like. But the law must keep its promises.

[-]AM10

He doesn't go into this in the book, but I am fairly sure that Harris would agree with your consequentialist take of "acting as if they had free will". I have heard him speak on this matter in a few of his podcasts around "the hard problem of consciousness" with Dennett, Chalmers and a neurosurgeon that I can't find the name of (I remember him being british). 

As I understand him, his view is to not view criminals (or anyone) as "morally bad" for whatever they have done, but to move directly on to figuring out the best possible way to avoid bad things happening again, to their future potential victims and to themselves. I think he sees this is as an important starting point in order to be able to be consequentialist about it at all. 

For example, if the best way to avoid criminals re-offending turns out to be to put them into a cushy, luxurious rehabilitation program, then in order to even consider this as an option, we must remove our sense of needing to punish them for being morally reprehensible.

So long as it doesn't increase the number of people committing crimes once to gain access to cushy luxurious rehabilitation programs, sure!

In my personal life, I do notice a tendency that when I do categorize people as being "morally wrong", this is more normally associated with wanting them to become morally right than wanting them punished for being morally wrong. The latter seems just one (probably ineffective) way to achieve the former. I don't seem to see this tendency in many other people around me, so I suspect I'm in a minority.

I don't think this relies on any particular position in the free will discussion though. I've seen some people "punish" objects for adversely affecting them by yelling or striking at them, and certainly not for reasons of the object having free will. It seems more of an innate urge than any philosophical belief.